Foldable support



Aug. 30, 1949. A. J. BRADFORD FOLDABLE SUPPORT Filed July 25, 1945 @www bw,

, Snventor qrJmo/nra i 03u/Jim@- (Ittornegs Patented Aug. 30, 1949 FOLDABLE SUPPORT Arthur J. Bradford, Wilmette, 111., assignorto Technical Service Inc., Detroit, Mich., a corporation of Michigan Application July 25, 1945, Serial No. 607,015

8 Claims.

This invention relates to supports and in particular to foldable or collapsible supports.

One object of this invention is to provide a foldable support having legs which are automatically spread apart as they are swung downwardly to their open positions.

Another object is to provide a foldablesupport having legs which may be folded from divergent extended positions to approximately parallel folded positions, with means for automatically spreading the legs apart as these are swung outwardly from their closed to their open positions.

Another object is to provide a, foldable support having pairs of legs disposed at opposite ends thereof and foldable from nesting positions outwardly and automatically to extended divergent positions.

In the drawings:

Fig. 1 is a side elevation of a preferred embodiment of the foldable support of this invention.

Fig. 2 is an end elevation of the foldable support shown in Fig. 1.

Fig. 3 is a horizontal section along the line 3--3 of Fig. 2.

Fig. 4 is a side elevation of the foldable support with the legs in their folded positions.

Fig. 5 is a bottom plan viewV of the foldable support of Fig. 4, with the legs in their folded and nesting positions. Y

Fig. 6 is a perspective view looking upward toward one end of the foldable support of Fig. 1 with the legs in their open and divergent positions.

In general, the foldable support of this in- 1vention consists of a base having a pair of legs secured at spaced locations thereon, together with a pair of pivoted connecting links which are in turn connected to a third link secured at its opposite end to the base. The linkage is so coni whichris pivoted a carrier IB having bent side structed and arranged that as the legs are swung outward from their nested positions wherein they lie approximately parallel to one another, they are automatically extended laterally into divergent positions. The support is adapted to a Variety of purposes and is especially well adapted for supporting projection screens.

Referring to the drawings in detail, Fig. 1 shows a preferred embodiment of the foldable support as consisting of a base I0 having brackets l I secured as at l2 to its opposite ends or at spaced locations thereon, the ends of the brackets I I being bent as at I3, and provided with aligned holes I4. Extending between the opposite holes Iii and secured therein is a pivot shaft I5 upon walls I'1 similar to the bent portions I3 of the brackets I I. The bent portions I1 are provided with aligned holes I8 through which the pivot shaft I5 passes, the portions I3 and l1 lying adjacent one another. The carrier I6 is provided with an inwardly bent tab I9 the ends of which serve as a stop.V

The carrier I6 is provided with spaced apertures 2i) for receiving pivot pins-2|. The latter pass through bores 22 in legs 23 of channel crosssection. The pivot pins 2| are spaced away from the lower edge 24 of the carrier I6 and also from the edgesrof the tab I9 so that these act as stops to limit the swinging of the legs 23 around their pivot pins 2l.

Pivotally-secured as at 25 and 26 to each adjacent pair of legs 23 are links 21 and 28 which are pivoted together at a common meeting point or pivot pin 29. The link 21 is extended beyond the pivot pin 29 in an extension 3Il having `a pin 3| which cooperates with a notch 32 in the link 28 to lock the links 21 and 23 together.

The pivot pin 29 also carries a yoke 33 pivotally mounted thereon and carrying a pivot pin 34 upon which one end of a link 35 is pivotally mounted. The other end of the link 35 is pivotally connected to a pivot pin 36 mounted upon the bent bracket 31 which is secured as at 38 to the support I 0 at a locationspaced away from the bracket I'I.

In operation, in their folded position the legs 23 lie adjacent and approximately parallel to one another with the legs 23 from one end of the base I0 lying between the legs 23 iromthe other end thereof. The links 21 and 28 are in their folded positions, and the operating links 35 lie between the legs 23 approximately along the center line of the support III.

To unfold the legs 23 and set up the support, the operator merelyswings the legs 23 outward iromthe position of Fig. 4 to that of Fig. 1. As the legs swing outward, the folded links 21 and 23 become extended -into a straight-line position (Fig. 6) as the operating link 35 pulls them into this position. As the links v21 and 28 thus `become aligned with one another, they push the legs 23 apart, bringing them into the positions shown in Figs. 2 and 6, and the pin 3I enters f draws them and the legs 23 together.

While a specic embodiment of the invention has been described and illustrated, it will be understood that various modifications may be made within the scope of the appended claims without departing from the spirit of the invention.

What I claim is:

1. In a foldable support, a base, a pair of elongated supporting members pivoted to said base on a lateralaxis relatively to said base, and additionally pivoted to said base on a longitudinal axis relatively thereto, and means for automatically moving said supporting members laterally away from each other in response to their being swung longitudinally awayAfrorn'sairl base'.`

2. In a ioldable support, abase, a' pair of elongated supporting members pivoted to said base on a lateral axis to said base Yand additionally pivoted to said base on a longitudinal axis relatively thereto, foldable vconnecting links' disposed between said supporting members remote 'from said pivot axes, and an operating link pivotally connected near one end tol said connectinglinks and pivotallyconnected near the other end-to said base at a location spaced apart from said pivot axes said loperating link being operative to automatically unfold said connecting links to effect lateral divergence of said supporting members in response to a longitudinal swinging of said supporting members relatively tov said base.

3. In a foldable'support, a base, a carrier pivoted to said base on a lateral axisrelatively to said base, a pair of elongated supporting meinbers pivoted to said carrier longitudinally relatively to said base, aY pair'of foldable links pivot-ed at their outer ends respectively to said supporting members at locations away from their pivots on said carrier andpivoted to one another at a common pivot near their outer ends, andan operating link pivotally connected at its outer end to said foldable links adjacent said common pivot and pivotally connected at its inner end to said base at a location remote from said previously-mentioned pivots, said operating link being operative to automatically unfold said foldable links in response to the swinging of said supporting members longitudinallyv relatively to said base'.

4. In a foldable support, a base, a carrier pivoted to said base on a lateral axis relatively to said base, al pair of elongated supporting members pivoted to said carrier longitudinally relatively to said base, a pair of foldable links pivoted at their remote ends respectively to said supporting members at locations away from their pivots on said carrier and pivoted to one another at their other ends, and an operating link pivoted near one end to said foldable links in the vicinity of their common pivot and pivoted near the other end to said base remote' from the pivot axes of said elongated supports` 5. In a foldable support, a base, two pairs of elongated supporting members pivoted to said Ybase on lateral axes relatively to said base at spaced locations thereon, and also pivoted to said base on longitudinal axes relatively to said base, a pair of foldable links pivoted at their outer ends respectively to each pair of said supporting members at locationsaway from their pivots on said base, each pair of foldable linksV being pivoted to one another at a common pivot near their inner ends, and an operating link pivotally connected '4 at its outer end to each of said pairs of foldable links adjacent said common pivot, said operating links being pivotally connected at their inner ends to said base at locations remote from said previously-mentioned pivots, said operating links being operative to automatically fold one pair of said supporting members into a position inside of the other pair in response to the swinging of both pairs of said supporting members toward each other into positions coextensive with said base.

6. In a foldable support, a base, two pairs of elongated supporting members pivoted to said base on lateral axes relatively to said base at spaced locations thereon, also pivoted to said base on longitudinal axes relatively to said base, one pair of said supporting members being foldable into a position inside of the other pair when both. pairs are folded toward each other into positions coextensive with said base, and means responsive to a swinging of said supporting members from said'folded positions toward positions transverse to said base for automatically eiecting lateral divergence of said supporting members.

7. In a foldable support, a base, a pair of carriers pivoted tosaid base on lateral axes relatively thereto at spaced locations thereon, a pair of elongated supporting members pivoted to each carrier on longitudinal axes relatively to said base, a pair of foldable links pivoted at their outer ends respectively to each pair oi said supporting members at locations away from their pivots on said carrier, each pair of foldable links being pivoted to one another at a common pivot near their inner ends, and an operating link pivotally connected at its outer end to each of said pairs of foldable links adjacent said common pivot, said operating links being pivotally connected at their inner ends to said base at locations remote from said previously-mentioned pivots, said operating links being operative to automatically fold one pair of said supporting members into a position between the other pair in response to the swinging of both pairs of said supporting members toward each other into positions coextensive with said base.

8. In a foldable support, a base, a pair of carriers pivoted to said base on lateral axes relatively thereto at spaced locations thereon, a pair of elongated supporting members pivoted to each carrier on longitudinal axes relatively to said base, one pair of said supporting members being foldable into a position between the other pair when both pairs are swung toward each other into positions coextensive with said base, and means responsive to a swinging of said supporting members from said folded positions toward positions transverse to said base for automatically effecting lateral divergence of said supporting members. ARTHUR J. BRADFORD.

REFERENCES CITED The Vfollowing references areV of record inV the lle of this patent:

UNITED STATES PATENTS Number Name Date 306,642 Porter Oct. 14, 1884 889,494 Van Halder June 2, 1908 932,702 Harris Aug. 31, 1909 1,382,707 Young June 28, 1921 

